Read GPIO problem
#14
(08-08-2017, 06:20 PM)pfeerick Wrote: My point the whole time as been simply that... if you export the pin, and it says that it's state is currently x, then it should damn well be x. not y, or z... x. The Raspberry Pi folks know that is what should be the case, so they made sure it was. Otherwise, the pin should have have a 'indeterminate' state, so that you know it hasn't been set yet. Wink 


My 4K R64 board came in yesterday ; so I played with it most of the night,  found that it does NOT have this issue.   If the pin is exported its direction is set IN, the active_low is set 0 and its value is set "1".  If the pin is grounded than the value changes to "0".  

So we need to get to the bottom of it;  is it a dts|dtb issue, a hardware issue with the PineA64+,  or a build issue ( something inconsistent with export somehow ).
marcushh777    Cool

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( I regret that I am not able to respond to personal messages;  let's meet on irc! )
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Messages In This Thread
Read GPIO problem - by shworker - 02-21-2017, 04:00 AM
RE: Read GPIO problem - by Techsensei - 02-21-2017, 06:41 AM
RE: Read GPIO problem - by shworker - 02-21-2017, 08:58 AM
RE: Read GPIO problem - by MarkHaysHarris777 - 02-22-2017, 04:23 AM
RE: Read GPIO problem - by aromring - 08-05-2017, 09:59 PM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-05-2017, 10:24 PM
RE: Read GPIO problem - by pfeerick - 08-06-2017, 01:33 AM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-06-2017, 10:38 AM
RE: Read GPIO problem - by pfeerick - 08-07-2017, 12:11 AM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-07-2017, 07:21 AM
RE: Read GPIO problem - by pfeerick - 08-07-2017, 07:21 PM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-07-2017, 11:10 PM
RE: Read GPIO problem - by pfeerick - 08-08-2017, 06:20 PM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-15-2017, 02:24 AM
RE: Read GPIO problem - by martinayotte - 08-17-2017, 01:21 PM

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